ABSTRACT
The official pesticide extraction techniques for complex matrices such as fat and tissues are tedious to perform, multi-step and can result in extracts containing interferences that can complicate the analysis. A new multiresidue technique for the extraction and quantitative gas chromatographic screening of 9 insecticides [lindane, heptachlor, aldrin, heptachlor epoxide, p, p['] DDE, dieldrin, endrin, p, p['] DDD and p, p['] DDT] as residues in chicken fat is presented. The 9 insecticides, plus dibutyl chlorendate internal standard, were fortified into half gram chicken fat and blended with 2 g C 18 [octadecylsilyl derivatized silica reversed phase material]. The C18/fat matrix blend was fashioned into a column by adding the blend to a 10 ml syringe barrel containing 2 g activated florisil. The insecticides were then eluted from the column with 8ml acetonitrile and a portion [2 micro L] of the acetonitrile elute was then directly analyzed by gas chromatography with electron capture detection. Unfortified blank controls were treated similarly. The resultant extracts contained the pesticide analytes [31.25 - 500 ng/g] that were free from interfering compounds when analyzed. Correlation coefficients for the 9 extracted pesticide standard curves [linear regression analysis, n = 5] ranged from 0.9957 + 0.0012 to 0.9999 + 0.0001. Average relative percentage recoveries [83 + 5.8 percent to 98 + 5.2 percent, n = 25 for each insecticide] inter assay [6.1 +3.2 percent to 15.9 + 6.7 percent, n = 25 for each insecticide] and intraassay [1.8 percent to 4.8 percent, n = 5 for each insecticide] variabilities were indicative of an acceptable methodology for the analysis and screening of these residues in chicken fat